John S. Gottschalk, 86, who served in the Interior Department for 25 years before retiring in 1970 as director of the U.S. Fish and Wildlife Service, died of cancer Aug. 13 at his home in Arlington.

His six years as the services' director, saw the first endangered species acts and a comeback by the nearly endangered whooping crane. The national wildlife refuge system added more than 500,000 acres of habitat, and urban wildlife programs were started. It was also during this time that DDT, which was lethal to bird reproduction, was banned as a pesticide.

Mr. Gottschalk had served as president of the American Fisheries Society and the Washington Biologists Field Club, and as both president and chairman of the Alliance of the Chesapeake Bay. He had served on the boards of the National Wildlife Federation and the Audubon Naturalist Society. He also had served as society conservation chairman.

Over the years, he received the Interior Department's Distinguished Service Award, as well as awards from such groups as the Wildlife Society, the International Association of Fish and Wildlife Agencies and the National Resources Council of America.

Mr. Gottschalk graduated from Earlham College in his native Indiana and received a master's degree in zoology from Indiana University. He began his career with the Indiana Conservation Department, where he was a park ranger, park naturalist and fisheries superintendent before World War II. During the war, he was a bacteriologist and lab director with the Schenley Corp., which was one of those firms producing antibiotics for the war effort.

He joined the Fish and Wildlife Service in 1945, serving in Montana before coming to Washington in 1951. He later became the first director of the new sport fisheries division.

In 1959, he went to Boston as director of the 11-state northeast region of the service. He became service director in 1964.

After retiring from the government, he worked from 1970 to 1973 as assistant to the director of the National Marine Fisheries Service. Then, until retiring in 1986, he served as an executive vice president and then counsel of the International Association of Fish and Wildlife Agencies.

He was an honorary life member of the American Fisheries Society, the Izaak Walton League of America and a member of the Cosmos Club.

Survivors include his wife of 62 years, Edith E., of Arlington; a son, Thomas A., of Washington; a daughter, Sara Nell Davis of Seabeck, Wash.; five grandchildren; and two great-grandchildren.